This summer, BBC’s “Science in Action” radio programme ran a number of items related to hydrology.

The link between floods and cholera
In September 1854, Dr John Snow discovered the cause of a cholera epidemic and removed the cause. A wonderful description of his detective work can be found in Edward Tufte’s The Visual Display of Quantitative Information. New research shows how cholera may survive outside of the human body and how flooding induces cholera outbreaks. Professor Islam explains how this knowledge may be used to design cholera early warning systems.Programme’s web page

The map that lead to Dr John Snow's discovery. Cholera cases are highlighted in black.

The science of flood prediction
On (probabilistic!) flood forecasting, warning and response in Pakistan and Bangladesh. Peter Webster, author of Were the 2010 Pakistan floods predictable? explains that forecasting alone is not enough, and how the entire flood forecasting, warning and response system is organised in Bangladesh.Programme’s web page

African rainfall data
If rain gauges are simply not there, observations from satellite may complement scarce records. David Grimes from Reading University’s TAMSAT Research Group explains how three decades’ worth of Cold Cloud Duration measurements is transformed into estimates of precipitation, and how that information may be used to calibrate models.Programme’s web page